I normally use a diatomaceus earth mix formulated by a fellow who is approx. 900 kms. away. Considering the bulk and weight its pretty expensive. I dont know the exact formulation but I am sure there is a cement part as he instructed me to manipulate the hardness and insulating property by adding cement. deatomaceus earth is not readily available in our place. In fact this fellow claimed that he is the only local producer.
So my question is. Do you have a mix that does not use DE but rather the abundant minerals such as lime, earth (what kind), sand (silica or whatever) and cement.
Gerry Parent wrote:Hello Julian, Quite frankly, I have never heard of anyone using diatomaceus earth in any part of a rocket mass heater. As serendipity had it though, there was an ad at the top of the page advertising it....here is the link : diatomaceus earth info
Have you read the Rocket Mass Heaters Builders Guide by Erica and Ernie Wisner? Soooo much information on rocket mass heaters that it is a wonderful resource not to have.
Burn tunnels are often made from firebrick, ceramic fiber, refractory materials made into a mold, perlite and clay...etc.
Perhaps if you give us more info on what you would like to do, we can better point you in the correct direction.
Yes I have used it many times and performs quite well. As my source said its his formula so basically his invention. I make customize equipment for costumers and as such burn tunnels are of different dimensions and shapes almost every time. This requires that I mix and mold the tunnels. I am not interested on RMH or heaters I am only interested on the materials that I can mix for the burn tunnels. We have refractory cement that cost rather high compared to yours. So basically I am on for something I can mix at a least cost.